Atomic Number
84
Polonium is a chemical element with symbol Po and atomic number 84, discovered in 1898 by Marie Curie and Pierre Curie. A rare and highly radioactive element with no stable isotopes, polonium is chemically similar to bismuth and tellurium.
84
209 u
post transition
solid
9.196 g/cm³
2, 8, 18, 32, 18, 6
Protons: 84 • Electrons: 84 • Neutrons: Varies by isotope
Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁴
1898 • Marie Curie, Pierre Curie